Internal-combustion engine



A. LLE6 AND 0. BARADAT.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED DEC-8, 1916.

1,355,484. Patented Oct. 12, 1920.

omrso sures ALBERTO LLEO Ann cmcmo BARAIDAT, or maonnona, scram.

INTERNAL-COMBUSTION ENGINE. I

Specification of Letters Patent.

Patented Oct. 12, 1920.

Application filed December 8, 1916. Serial No. 185,798.

To all whom it may concern Be it known that we, ALBERTO LLE and CLAUDIOBARADAT, subjects of the King of Spain, residing at Barcelona, Spain,have invented certaln new and useful Improvements in Internal-CombustionEngines, of which the following is a specification.

Our invention relates to multicylinder internal combustion engines, andits object is the construction of an engine of this class for specialuse on motorcars, motor-boats and flying machines, andcapable of beingput to many other uses.

Our invention essentially consists in placing the several cylinders ofthe engine in a paralleldirection with its shaft. and distributed aroundthe same, in connection with a ring-piece placed on acircular supportfixed to the shaft and forming with it a certain angle. The abovementioned-ring-piece is joined with the connecting-rods of the severalcylinders and mounted in such a 7 way as to prevent it goin around theshaft,

but allow-ing it to oscil ate following the movements of the connectingrods.

Owing to the disposition of this ring-piece joined with theconnecting-rods of the cylinders, and to the circular support fixed onthe shaft at a certain angle, the rectilinear movement of the pistons istransformed into a rotatory movement of the engine shaft.

Another characteristic of our invention is that the distributionmechanism for the operation of the inlet and exhaust valves is alsodisposed around the engine shaft in such a way that the cams that liftthe valves are placed on a sleeve which -is rotated around the shaftthrough a differential gear giving the correct speed required for theoperation of the valves. All the inlet valves have a communication witha circular passage to which is connected the intake pipe that draws inthe explosive mixture; the exhaust valves have a similar communicationwith another circular passage joined with the exhaust pipe that drivesout the burnt gases.

This engine may be single or double, or in other words built with one ortwo sets of cylinders distributed around the shaft. In the first casethe shaft has only at one of itsends one circular supportwith the cor-,

responding ring-pieces to which theconnectin rods of the istons arejoined; the circuIar passages or the inlet and exhaust valves beingarranged at the other end of.

the engine. In a double engine, the cylinders on both sets are sodisposed that each cylinder of one set is built on the same axis as thecorresponding cylinder on the other set and opposite to it; the engineshaft having at each end a circular support with the ring piece joinedwith the connecting rods of the cylinders. Each pair of oppositecylinders in this case works simultaneously having a common head andcombustion space on which are placed the inlet and exhaust ports and thesparking plug for igniting the mixture. Owing to this disposition andthe simultaneous firing of each pair of opposite cylinders theaxialstrains produced by the explosion are efficiently checked. Ourinvention is represented in the accompanying drawings in the form of adouble engine, that is, an engine with two symmetrical sets ofcylinders.

Figure l is a sectional View along the enig. 2 is a sectional view alongthe line I of Fig. 1., Fig. 3 is another sectional view along the lineIII of Fig. 1.

- The engine shown 1s a double engine; the

series of combustion chambers 2 disposed around the same, in parallelrelationship with each other. On either side of the combustion chamlbers2 are ders 1, each cylinder having its piston 7 thus, as shown in Fig.2, seven pairs of' cylinders are distributedaround the shaft'40.

placed the cylinno shaft, with some parts broken awa I shaft 40 may beseen in the drawings, with a rod 9 articulated by a spherical knuckle 8;the other end of theconnecting rod forming also another sphericalknuckle. 10, which is dul articulated with the ring 11.

fl his rests on the circular support 12-13 which is fixed to the shaftby means of its hub 19 and a key. The ring 11 bears on the circularsupport 12 by means of the ball bearings 14-15 and on the "circularsupport 13 by means of ball bearing 16. The Y ring 11 has on its flangea roller 17 that fits inside the guide 18 so that the ring'cannot turnaround and has only an oscillato movementimparted by the connecting r0 s'9. Only onectonnecting rod 9 belonging to piston 2, is shown in ig. 1;but is easilycircular support 12 and the ring 11 takes up the radialthrust; and the ball bearings 15 and '16 take up the-axial stresses. The

circular support 12 is built with reinforce- I with another circularments 20 so as to avoid deformation that might be produced by the thrustof the explosion.

The circular support 12--13 is inclined to the shaft accordingto thestroke of the pistons. The ring 11 follows the same angle as thecircular support.

The sleeve or hub 19, made in one piece with the circular support, isfixed to the shaft 40 having at its end 21 the propeller not shown inthe drawing, or other mechanism for the transmission of the movement.This sleeve has at the inner end a bevel gear 22 whichmeshes with gear'26, fixed to the engine body, bymeans of the intermediate planetarypinions 27 mounted on pins over the sleeve 28 concentric with the shaft40 on which it turns around.

Two ball bearings 24 and 25' are interposed between the sleeve 19 andthe body of the engine 39; another ball bearing 23.

is placed between the sleeve 19 and the a cover of the engine 41; this,not only enables the rotatory movement of the sleeve 19, but also takesup the axial stress which tends to thrust apart the extreme circularsupports although in the case of a double engine, the extreme circularsupports being both fixed to the shaft 40-, the stresses produced by thethrust ofthe-two sets of pistons are most efficiently balanced.

The sleeve 28, on which is mounted the planetary pinion 27, turns aroundat half the shaft s eed owingto the differential gear formed by bevelgears ,2226 and the planetary pinions 27.

, The sleeve 28 carries the cams 29; the number of these cams beingequal to the number of airs of cylinders of the engine; each cylindlirhas a-shaft 30 which carries the small arms 32 with a roller placedbetween them, which roller bears 'on the cams 29. Each shaft 30 has alever 33 for the operation of the corresponding exhaust valve 3.

. On the sleeve 28 is further arranged a number of cams 38 e ual to thenumber ofpairs of cylinders; ach of the cams 38 cooperates with a roller42 mounted on the arms of a shaft 31 of a corresponding pair ofcylinders, and actuates a lever 43 carried by the shaft 31 to operatethe inlet valve 4.

v All the levers '33 are situated in one plane as shown in the viewin'Fig. 2 and all of thelevers 43 are similarly situated; but all of thecame 29 and 38 are placedin different planes or cross sections ofthe'engine, the

corresponding rollers 32 and 42 for every cated with a circular passage34 to which is connected the exhaust pipe 35'; all the inlet valves '4having a similar communication 7 passage to which is attached the intakepipe 37.; i T,

The accessory parts of the engine, such as the magneto, oil pump, waterpump and others, are not shown in thedrawings, as it has not been deemednecessary for the understanding of, our invention.

The working of a double engine, as specified above, is as follows: Whenthe explosion takes place in the combustion space 2 the two pistons 7are thrust in opposite dimotions and the corresponding connecting rods 9that are now at the end of the stroke, or dead point, press forward thecorresponding ring pieces 11. Each ring, by the the circular support 12on which it rests,

throughthe ball bearing 15; but, as the roller 17 with its guide 18prevents this rotatory in every one of the points of the ring 11 wherethe spherical knuckles for the articulation of the several connectingrods of-tlie engine are placed; as a' result ofit, this oscillatorymovement of the ring will take place causing at the same time acontinual variation of theangle formed by the ring plane and the shaft40; this oscillatory movement, as it has been sald before, beingtransformed into a rotatory movementofthe circular support 12 andthereby of the sleeve 19 and theengine shaft 40.

The ball bearing 16 is not absolutely necessary as the thrust of theconnecting rods is directly applied on the circular support 12, but themomentum of the pistons might produce at certam moments an oppositereaction .on the circular support 13.-

As to ball bearing15 its function is the one of an ordinary ballbearing, as the ring 11 is not revolving and on the contrary thecircular support 12 turns around on 1t.

We have shown and described a double engine, or an engine with two setsof cylinders, but, it is easily understood, that an cylinders. In thiscase one end of the-en- 'gine carries the circular support with theengine. may be built with onlyone set of I 90 thrust imparted to it, hasa tendency to go around the shaft 40 slipping parallelly over theconnecting rods generating the rotatory movement of the shaft; thecircular passages that communicate with the inlet and exhaust valvesbeing placed at the other end.

When applying our invention use could also be made of the well knownprinciple of the inversion of the movement; this could be done by fixingthe engine shaft and letting the engine go around; the body of theengine bearing in this case, the propeller or other mechanism for thetransmission of the movement. This could not alter the essential part ofthe invention; it only being necessary to arrange a hollow shaft for theinlet of the mixture, as usually done in this type of engines.

The type of engine shown in the accompanying drawings, and hereindescribed, is only one example of execution of the invention, as it iseasily understood, that it is possible to vary the disposition ofcertain parts of the engine, for instance by using rotatory valves,without altering the essentional conditions of the invention.

We claim:

1. In an internal combustion engine, a plurality of cylinders placedaround the engine shaft and parallel thereto, a pluralityof pistons andconnecting rods in said cylinders, means to transmit to the engine shaftthe motion of said pistons, transforming it into a rotary movement, aplurality of combustion chambers for the several cylinders and providedwith spark plugs and inlet and exhaust valves, all said valves beingdisposed radially with their stems directed toward the engine shaft, anannular conduit for the mixture of air and fuel communicating with allthe inlet valves, an annular conduit communicating with all the exhaustvalves and connected to the exhaust pipe, both conduits being disposedbetween the engine shaft and the combustion chambers, a sleeve looselymounted on the engine shaft and rotated to actuate the several valves, aplurality of cams arranged on said sleeve, a plurality of shaftsparallel to the engine shaft, each provided with an arm engaging with acam on said sleeve and with another arm that actuates the correspondingvalve, said sleeve and said shafts being disposed in the space'betweenthe cylinders and the engine shaft.

2. In an internal combustion engine, a plurality of cylinders arallel tothe engine shaft and placed in pairs around it, the cylinders of eachpair being juxtaposed coaxially, a plurality of pistons and connectingrods in said cylinders, means adapted to impart to the engine shaft themotion of said pistons, transforming it into rotary movement, acombustion chamber connecting the head of each pair of cylinders andprovided with a spark plug and inlet and exhaust valves, all said valvesbeing disposed radially and with their stems directed toward the engineshaft, an annular conduit sleeve adapted to be rotated from the engineshaft by means of a differential gear, a plurality of cams on saidsleeve adapted to actuate all the inlet and exhaust valves, a shaft foreach valve, said shaft being parallel to the engine shaft and providedwith an arm on one end which is actuated by the corresponding cam and anarm on the other end which transmits this motion to the valve, saidsleeve, differential gear and shafts being disposed in the space betweenthe cylinders and the engine shaft.

3. An internal combustion engine having a plurality of cylindersdisposed around the engine shaft and parallel thereto, said cylindersbeing arranged in opposed pairs each pair having a common combustionchamber, a plurality of pistons in said cylinders connected with theengine shaft so as to drive the same, and intake and exhaust valves forsaid chambers, in combination with valve controlling means disposedradially within the space between the engine shaft and the cylinders,and axially within the length of the cylinders, said valve controllingmeans comprising a sleeve formed with cams, mounted on the engine shaftand driven thereby to rotate relatively thereto, and

- a plurality of cylinders disposed around the engine shaft and parallelthereto, said cylinders being arranged in opposed pairs, each pairhaving a common combustion chamber, a plurality of pistons in saidcylinders connected with the engine shaft so as to drive the same,intake and exhaust valves for saidchambers, an annular passage for theincoming fuel and air, another annular passage for the exhaust, saidpassages being disposed in the space between the opposed cylinders andwithin the combustion chambers, in combination with valve controllingmeans disposed radially within the space between the engine shaft andthe cylinders, and axially within the length of the cylinders, saidvalve controlling means comprisinga sleeve formed with cams, mounted onthe engine shaft and driven thereby to rotate! relatively thereto, andshafts parallel to the engine shaft and each provided with an arm forengaging one of said cams and another arm for engaging the stem of oneof the valves, the annular passages for fuel and exhaust being disposedcloser to the cylinder of the engine than the valve operating means.

5. An internal combustion engine having a plurality of cylindersdisposed around the engine shaft and parallel thereto, said cylindersbeing arranged in opposed pairs, a plurality of-pistons in saidcylinders connected with the engine shaft so as to drive the same, andvalves for said cylinders, in

combination with valve controlling means disposed radially within thespace between the engine shaft and the cylinders and axiall within thelength of the cylinders.

6. 11 internal combustion engine comprising a mechanism includingcasing, a plurality of cylinders disposed around the engine shaft andparallel thereto and within the casing, a plurality of pistons in saidcylinders connected with the engine shaft so as to drive the same and apair of valves for each cylinder disposed between the pistons thereinand having stems extending from the valves radially of the cylinders,said casing so formed as to provide an internal chamber between thecylinders on opposite sides of the shaft and of substantially the lengthof the cylinders, valve controlling means being disposed within saidchamber.

7. An internal combustion engine according to claim 6, having aninwardly extending flange on the casing, which flange divides thechamber into two compartments, the one of which houses the valvecontrolling means, driving mechanism for said means being housed in theother compartment.

8. An internal combustion engine according to claim 7 in which the valvecontrolling means comprises a sleeve rotatably mountedon the engineshaft, cams on said sleeve, a shaft parallel to the engine shaft andhaving an arm engaging one of said cams and an arm engaging one of thevalve stems, said sleeve provided with planetary pinion, a gear fixed tosaid flange and a gear rotating with the engine shaft, said planetarypinions meshing with said engine shaft gear and said stationary gear,said gearing housed in said other compartment.

9'. In an internal combustion engine and in combination, a casing, aplurality of cylinders around the engine shaft and parallel thereto and.arranged in opposed pairs, a plurality of pistons in said cylindersconnected with the engine shaft so as to drive the same, intake andexhaust valves for said cylinders, an internally extending centralflange on the casing, a similar flange on the casing to one side of thefirst mentioned flange, a third flange on the casing adapted to supportan .engine shaft bearing, valve controlling means in a compartmentprovided between said first and second mentioned flanges, drivingmechanism for said of said cams and an arm for engaging one of saidvalves.

10. In an internal combustion engine, the combination of a substantiallycyllndrical,

mechanism-containing casing, a shaft 'rotatably mounted for movementabout the axis of the casing, a plurality of explosive said shaft, areeling plate at each end of the casing operatively connected fortranslating the reciprocatory movement of the adjacent pistons intorotary movement of the shaft, shaft-driving and valvular-controlmechanisms having a looking-glass symmetry on opposite sides of a medialplane perpendicular to the axis and passing through the explosivechambers, said shaft-driving mechanism including a pair of balancedpistons in each chamber, valvular mechanism on each side of the medialplane including avalve for each chamber, valvular actuating mechanismfor each valve and a single cam control sleeve provided with a pluralityof cams one for each of the several valvularactuatin mechamsms, saidsleeve carried bythe sha positioned between thereeling plates and adrive at one end of the sleeve for driving the same from the shaft.

11. In an internal combustion engine, the combination of a driven shaft,a plurality of explosive cylinders disposed about the shaft andextending longitudinally thereof,

shaft-driving mechanism, and valvular control mechanism each having alooking-glass symmetry on opposite sides of a medial plane perpendicularto the shaft and passing through the explosive chambers, saidshaftdriving mechanism including balanced pistons in each cylinder and areeling plate at opposite ends of the cylinders, and operativelyconnected to translate reciprocatory movement of the adjacent pistonsinto rotary movement of the shaft, said valve actuating means includinga valve for each cylinder, a set of cams, one cam for-each valve andconnected to work in unison, said sets being each carried by the shaftand spaced apart thereon between the reeling plates and a plurality ofcam controlled valve actuating chambers within the casing adjacent thecentral portion of the same and encircling a driving connection betweensaid shaft and said sets of cams connected to the shaft adjacent one endthereof.

12. In an internal combustion engine, the combination of a driven shaft,a plurality of explosive chambers encircling said shaft and extending inparallel relation thereto, a pair of balanced pistons in each cylinderand means includian a reeling plate on opposite sides of the chambersfor translating the reciprocatory movement of the adjacent pistons intorotary movement of the shaft, each cylinder provided with a valvemounted for movement to and from its seat radially of the shaft, saidvalves being disposed substantially in a plane perpendicular to theshaft, a cam sleeve positioned on the driving shaft between the reelingplates and provided with a plurality of longitudinally spaced apart camsoffset circumferentially in order to cause a periodic movement of thevalves, and a connection between each cam and a corresponding valvewhereby the rotary movements of the cam shaft is translated intomovements of the valves in the chambers, and means for driving the camshaft from the driven shaft.

13. In an internal combustion engine, the combination of a driven shaft,a plurality of explosive chambers encircling said shaft and extending inparallel relation thereto, a pair of balanced pistons in each cylinderand means including a reeling plate on opposite sides of the chambersfor translating the reciprocatory movement of the adjacent pistons intorotary movement of the shaft, each cylinder provided with a pair ofradially movable valves positioned relatively close together, the valvesconstituting two sets disposed in parallel planes perpendicular to theshaft, each of the valves provided with a valve actuating meansextending longitudinally of the shaft and in an outward direction awayfrom the other valve in the cylinder and revolving cams spaced apartlongitudinally of the driven shaft between the reeling plates andoperatively connected to be driven in unison with the driven shaft, saidcams being in control of said valve actuating means whereby the closelypositioned valves are actuated by cams distributed along the len h ofthe driven shaft facing the length 0 the explosive chambers.

14. In an internal combustion engineof the four-cycle type, thecombination of a driven shaft, an explosive cylinder extendinglongitudinally of the shaft and spaced therefrom to provide a valvularcontrol containing space therebetween, a pai of balanced pistons in saidc linder, me s at opposite ends of the cylinders for ranslating thereciprocatory movement f the adjacent pistons into rotary movement ofthe shaft, said cylinder provided with a valve having a stem projectingradially from the cylinder into the said space, a valvular controlincluding a cam mounted on the portion of the shaft within the length ofthe cylinder and operatively connected to be rotated by the shaft andvalve actuating means contained in the space between the cam andcylinder connecting the cam with said valve stem, whereby the rotationof the shaft will cause the valve to function periodically.

15. In an internal combustion engine, of the four-cycle type, thecombination of a member mounted for rotary movement about its axis andprovided with two sets of valve controlling cams mounted thereon, aplurality of explosive chambers extending parallel to said cam memberand encircling the same, a pair of balanced pistons in each chamber, twosets of valves disposed in parallel planes perpendicular to the cammember and constituting inlet and exhaust valves for each chamberopening into the same between the pistons therein, and positionedrelatively close together, certain of the controlling cams being spacedlongitudinally of the valves controlled thereby and connecting membersextending longitudinally of the member and actuated by the cams to causethe valves to actuate in proper timed sequence and mechanism driven fromsaid pistons.

16. In an internal combustion engine, the combination of a driven shaft,a plurality of cylinders disposed about said shaft and extendingparallel thereto, a casing provided within its outlines with an annulargas-containing passageway provided with ports opening into each of saidcylinders and disposed in a plane perpendicular to the shaft, valves forcontrolling the ports, means actuated from the shaft for controllingsaid valves, a pair of pistons in each cylinder disposed on oppositesides of the valve-controlled port in the chamber and a drivingconnection between the shaft and each of said pistons.

17. In an internal combustion engine, the combination of a driven shaft,a plurality of cylinders disposed about said shaft and extendingparallel thereto, a casing provided within its outlines with an annulargas-containing passageway provided with ports opening into each of saidcylinders and disposed in a plane perpendicular to the shaft, Valves forcontrolling the ports, means actuated from the shaft for controllingsaid valves, a pair of pistons in each cylinder disposed on oppositesides of the valve-com" trolled-port opening into each cylinder and adriving connection between the shaft and each of said pistons, and saidcasing provided with a radially extending conduit opening from saidannular-gas-containing passage to the exterior of the engine.

18. In an internal combustion engine, the

combination of a driven shaft, a plurality of cylinders disposed aboutsaid shaft and extending parallel thereto, a casing provided within itsoutlines with two annular gas containing passageways one adapted toconstitute the fuel intake and the other adapted to constitute the fueldischarge, ports opening from each of said passageways into eachcylinder, valves for controlling said ports, a pair of pistons in eachcylinder, disposed on opposite sides of the pair of valve controlledports in each cylinder, a reeling plate connecting between each pistonand the shaft and means between the reeling plate for actuating thevalves in proper sequence from the shaft to alternately admit fuel toeach cylinder in succession and to discharge the fired fuel in eachcylinder.

19. In an internal combustion engine of the four-cycle type, thecombination of a casing provided with a driven shaft, an annulargas-containing passageway disposed in a plane perpendicular to theshaft, a phi-- rality of explosive chambers encircling said annularpassageway, ports in the inner side of said chambers, providingcommunication between said passageway and each of said explosivechambers, valves for controlling said ports, a pair of piston cylindersdisposed lengthwise of the shaft at opposite ends of each of saidchambers and open thereto whereby both pistons are actuated by theexplosion in the common, chamber, said piston cylinders having a greatercrosssectional area than the corresponding explosive chamber, a drivingconnection between each piston and the shaft, and a valvular controldriven from the shaft and operatively connected to the valves to actuatethe same in theirproper sequence.

20. In an internal combustion engine, the combination of a casing, ashaft rotatably mounted in said casing at two spaced apart points, aplurality of explosive chambers encircling the portion of the shaftbetween said mounting points, piston cylinders extending lengthwise ofthe shaft at opposite ends of said explosive chambers, balanced pistonsin each of said cylinders, means including reeling plates positioned tothe outside of each of said points and disposed in close juxtapositionthereto for translating the reciprocatory movement of the adjacentpistons into rotary movement of the shaft, a gas passageway encirclingthe shaft and encircled by the circle of explosive chambers, a valvecontrolling sleeve loose on said shaft and including a plurality ofcams, a differential driving connection between the sleeve and the shaftositioned relatively close to one of said sha t mounting points, valvecontrolled ports between said gas passageway and each of said explosivechambers and valve control means for each valve operatively associatedwith the cams on the sleeve to control the passage of gas from thepassageway to the several explosive chambers.

21. In an internal combustion engine, a main casing, including an inner,cylindrical mechanism containing shell, a driven shaft disposed in theaxis of said shell, a pair of anti-friction mountings for the shaftspaced apart in said shell to support the shaft from the casing, aplurality of longitudinally extending piston cylinders encircling saidshaft between its mountings, fuel controlling valves for the cylindershaving stems proecting into the interior of said shell, a valvecontrolling sleeve positioned on the part of the shaft between themountings and operatively connected to be driven by the shaft and valvestem actuating connections between each valve stem' andi said sleeve.

22. In an internal combustion engine, the combination with a mainsubstantially cylindrical, centrally disposed casing, shaft bearings atopposite ends of said casing, end heads at opposite ends of said casingand each provided with a shaft bearing, a shaft mounted in the fourbearings and projecting exteriorly of the end heads, said casing formedwithin its outlines with a centrally disposed gas passageway encirclingsaid shaft, and with a plurality of explosive chambers encircling thegas passageway, valve controlled means for placing the passageway influid communication with the explosive chambers, a pair of pistoncylinders confined within the outlines of the main casing and disposedat opposite longitudinal ends of each of said explosive chambers, andeach piston cylinder opening into the adjacent end head, a piston ineach of said cylinders having its rod projecting therefrom substantiallyparallel to the shaft, and means in each end-head and including awabbling plate for translating the recipro catory movement of thepistons into rotary movement of the shaft.

23. An internal combustion engine casing including three main pieces, acentral strain receiving cylindrical piece and two end pieces, saidcentral piece being in the form of a hollow casting provided with anannular gas conducting passageway, a ring of explosive chambersextending in longitudinal, parallel relation to each other andencircling said .conducting passageway, the partition between thepassageway and the chambers provided with a ring of valvecontrolledports for placing'the passageway in fluid communication with each of thechambers, said central piece provided with means for supporting balancedpistons at opposite ends of each of said explosive chambers and saidcentral piece coacting with the end pieces at each end for supportingpiston driven mechanism in each end piece.

24. An internal combustion engine includhaust chamber, the space withinthe inner shell constituting a valve-control mechanism containing space.

25. An internal combustion engine including a cylindrical casting formedin effect of three concentrically disposed shells, means for dividingthe space between the outer and the intermediate shell into a pluralityof explosive chambers, the space between the intermediate and the innershell being divided perpendicularly to the axis of the casing to form afuel chamber and an exhaust chamber, the space within the inner shellconstituting a valve-control mechanism containing space, said outershell provided with openings extending therethrough into the explosivechambers and adapted to receive spark plugs for firing the charge in thechambers and disposed in position accessible from the outside of theengine.

26. In an internal combustion engine of the balanced piston type, thecombination of a driven shaft, a plurality of explosive chambersencircling said shaft and spaced therefrom, a pair of piston cylindersopen to said explosive chamber at opposite ends thereof, pistons mountedin said cylinders, a driving connection between said pistons and saidshaft, a gas passageway disposed within the circle of said explosivechambers and positioned between the ring of chambers and said shaft,radially extending valves for controlling the gas flow between thepassageway and the explosive chambers, mechanism for actuating saidvalves disposed between the shaft and the valves and operativelyconnected to the shaft to be driven thereby, the outer wall of one ofsaid explosive chambers having an opening facing one of the valvestherein and having a dimension to permit the valve to be withdrawn fromits seat through said opening without affecting said valve actuatingmechanism. i

27. In an internal combustion engine of the balanced piston type, thecombination of a drivenshaft, a plurality of explosive chambersencircling said shaft and spaced therefrom, a pair of piston cylindersopen to said explosive chamber at op thereof, pistons mounted in sa1 adriving connection between said and said shaft, a within the circle oand positioned between the ring of chambers and said shaft, radiallyextending valves .forcontrolling the gas flow between the pascylinders,pistons fgas passageway dlsposed osite ends said explosive chamberssageway and the explosive chambers, meeh-' radiating extension tendingto cool the outer wall of the explosive chamber; 7

28. In an internal combustion engine of the balanced piston type, thecombination of a driven shaft, a plurality of explosive chambersencircling said shaft and spaced therefrom, a pair of piston cylindersopen to saidexplosive chamber at opposite ends thereof, pistons mountedin said cylinders, a driving connnection between said pistons and saidshaft, a gas passageway dlsposed within the circle of said explosivechambers and positioned between the ring of chambers and said shaft,radially extending valves for controlling the gas flow between thepassageway and the explosive chambers, said valves being provided withactuating stems, and extending radially toward the shaft, and valveactuating means disposed between the shaft and the valve stems, adaptedto bear on the stems to actuate the same but otherwise free of the stemswhereby any one of the valves may be readily dismounted withoutaffecting the action of said means on the remaining valves.

29. In an internal combustion engine, the

combination of a cylindrical casting including in effect threeconcentrically disposed shells, means for dividing the space between theouter and the intermediate shells into a plurality of explosivechambers, the space between the intermediate and the inner shellconstituting a gas passageway, the intermediate shell provided with aport for placing'one of the chambers in fluid com-' the outer andtheintermediate shells into a 4 plurality of explosive chambers, thespace between the intermediate and the inner shell constituting a gaspassageway, the intermediate shell" provided with a port for,

placing one of the chambers in fluid communication with the passageway,a radially extending valve for controlling said port, i

the outer shell opposite said valve provided with an opening affordingaccess to the valve, means for normally closing said opening, and meansfor controlling said valve housed within the inner shell.

31. In an internal combustion engine, the combination of a cylindricalcasting including in effect three concentrically disposed shells, meansfor dividing the space between 32. In an internal combustion engine ofthe balanced piston type, the combination of a plurality of explosiveand expansion chambers disposed concentrically about an axis ofreference and spaced therefrom, said chambers each including a pair ofalined piston cylinders and a common explosive chamber therebetween andwith the inner wall of the explosive chambers spaced from the axis adistance greater than thefcorresponding distance of the inner wall ofthe piston cylinders thereby to form an annular space between the pistoncylinders, means providing two annular passageways within said space,one of said passageways con stituting means for supplying fuel to theseveral explosive chambers and the other passageway constitutinga meansfor con-- chambers disposed concentrically about an' axis of referenceand spaced therefrom,said chambers each including a pair of alinedpiston cylinders and a common explosive chamber therebetween and withthe inner wall of the explosive chambers spaced from the axis a distancegreater than the corresponding distance of the inner wall of the pistoncylinders thereby to form an annular space between the vpistoncylinders, means providing two annular passageways within said space,one of said passageways-constituting means for supplying fuel to theseveral explosive chambers and the other passageway constituting a meansfor conducting the spent gas from said explosive chambers, valves forcontrolling the. flow between said explosive chambers and saidpassageways, and talve control mechanism disposed in the spacebetweenthe axis and the annular gas and fuel conducting passageways andoperatively connected to said valves to cause the same to function intheir proper sequence.

